Autologous cryopreserved leukapheresis cellular material for chimeric antigen receptor-T cell manufacture.

Tisagenlecleucel, a CD19-specific autologous chimeric antigen receptor (CAR)-T cell therapy, is efficacious for the treatment of relapsed/refractory B-cell precursor acute lymphoblastic leukemia and diffuse large B-cell lymphoma. The tisagenlecleucel manufacturing process was initially developed in an academic setting and subsequently transferred to industry for qualification, validation and scaling up for global clinical trials and commercial distribution. Use of fresh leukapheresis material was recognized early on in the transfer process as a challenge with regard to establishing a global supply chain. To maximize manufacturing success rates and to overcome logistical challenges, cryopreservation was adapted into the Novartis manufacturing process from the beginning of clinical trials. Tisagenlecleucel manufactured in centralized facilities with cryopreserved leukapheresis material has been used successfully in global clinical trials at more than 50 clinical centers in 12 countries. Cryopreservation provides flexibility in scheduling leukapheresis when the patient's health is optimal to provide T cells; it also provides protection from external factors, such as shipping delays, and removes manufacturing time constraints. Several studies were performed to establish comparability of fresh versus cryopreserved leukapheresis material, to evaluate and optimize the cryopreservation process, to determine the optimal temperature and maximum hold time prior to cryopreservation and to determine the optimal temperature range for shipment and storage. Using the current validated industry manufacturing process, high success rates were achieved with regard to manufacturing tisagenlecleucel batches that met specifications and were released to patients. Consistent product quality and positive clinical outcomes support the use of cryopreserved non-mobilized peripheral mononuclear blood cells collected using leukapheresis for CAR-T cell manufacturing.

Current status and future perspectives of leukocytapheresis for inflammatory bowel disease.

Ulcerative colitis (UC) and Crohn's disease (CD) comprise the idiopathic inflammatory bowel diseases (IBD) of the gut. The etiology of IBD is poorly understood, but an autoimmune disturbance has been suggested to play an important role in this incurable disease. Extracorporeal leukocytapheresis (CAP) is an additional adjunct for IBD patients refractory to other conventional therapies, including steroids. The primary aim of CAP should be to suppress such unwanted immunological response by removing circulating inflammatory cells from the blood stream. The first decade has been passed since CAP was approved by Japanese social health insurance policy. It is therefore now an appropriate opportunity to upgrade and summarize our current understandings and/or future perspectives of this unique non-pharmacological and non-surgical strategy for IBD patients. According to several clinical and basic research reports, an early introduction of CAP should produce higher efficacy as compared with CAP applied sometime after a clinical relapse. Likewise, CAP therapy adjusted to patients' body-weight as well as two treatment sessions per week (intensive regimen) should benefit the efficacy rate. The etiology of IBD is not fully elucidated yet. As a result, the major therapeutic strategies in the Western world have been immunosuppressive therapy, including biologics. CAP is an unusual treatment modality for IBD because it seems to have both effectiveness and safety, which should generally be balanced in this type of illness. We now have to develop future strategies with and without combining biologics to improve the quality of life of IBD patients.

Beyond dialysis: current and emerging blood purification techniques.

Extracorporeal blood purification using various techniques and hardware is a major part of the modern day practice of clinical nephrology. Although the various modalities of hemodialysis and hemofiltration are the most commonly used extracorporeal therapies in clinical nephrology, blood purification using other techniques have become necessary to remove pathogenic, toxic, or waste substances not easily cleared by hemodialysis or hemofiltration due to factors such as molecular size, protein binding, and lipid solubility. The following review is an up to date summary of extracorporeal therapies, beyond hemodialysis and hemofiltration, in current clinical use as practiced by nephrologists and others in the United States and beyond. This comprises therapeutic apheresis (plasma exchange and cytapheresis), plasma adsorption, hemoperfusion, and the bio-artificial devices.

New and emerging therapies for inflammatory bowel diseases.

The inflammatory bowel diseases have undergone an explosion of discovery in the last 10 years. The overwhelming focus of this has been in genetics and immune mechanisms of disease. While the former has provided critical information on predisposing factors, the latter has resulted in a panoply of novel immune-based therapies and technologies. These range from an improved approach to the use of conventional immunomodulators, such as azathioprine and 6-mercaptopurine, to commonplace availability of anti-tumor necrosis factor agents such as infliximab and adalimumab, through to small molecule inhibition of immune mediators. Unusual treatments, such as helminth infestation, stem cell transplantation, and leucocytapheresis, all derive from the burgeoning understanding of pathogenesis. Most important to our successful use of these therapies will be a fundamental understanding of the patient phenotypes and genotypes that will dictate particular treatment approaches in the future.

Developments in the apheresis procedure for the treatment of inflammatory bowel disease.

Initially used to treat rheumatoid arthritis, nonselective therapeutic leukocytapheresis was applied to the treatment of inflammatory bowel disease (IBD) as early as the 1980s. Since then, the process has been further refined and 2 blood perfusion systems using membrane filtration are presently employed in Japan and Europe for the selective removal of leukocytes in patients with IBD: Cellsorba is a column of polyethylenephtarate fibers that captures lymphocytes and granulocytes, and Adacolumn is a column of cellulose acetate beads that selectively adsorb granulocytes and monocytes. These systems overcome the limitations of centrifugation. Leukocytapheresis has been shown to exert an overall anti-inflammatory effect, as peripheral leukocytes demonstrated a diminished capacity to produce inflammatory cytokines such as tumor necrosis factor-alpha, interleukin (IL)-1, IL-6, IL-8, and IL-1beta. In addition, down-regulation in the expression of adhesion molecule L-selectin and a shift toward a more immature granulocyte phenotype were observed in the peripheral blood. The safety and beneficial therapeutic effect of leukocytapheresis in IBD are being investigated further.

Safety and efficacy of allogeneic PBSC collection in normal pediatric donors: the pediatric blood and marrow transplant consortium experience (PBMTC) 1996-2003.

The use of peripheral blood stem cells (PBSC) for allogeneic transplants in adults has greatly increased. This trend is reflected in pediatrics, where healthy children increasingly are donating PBSC or donor lymphocyte infusion (DLI) via apheresis for use by ill siblings. There is a potential concern that the risks of PBSC collection may differ for pediatric donors. However, no large studies have assessed safety issues in this population. To address this need, we reviewed 218 (213 PBSC, five DLI) collections in 201 normal pediatric donors (8 months to 17 years, median 11.8 years) at 22 institutions in the Pediatric Blood and Marrow Transplant Consortium. Donors received a median of 4 days of growth factor, and mean collection yield was 9.1 x 10(6) CD34+ cells/kg recipient weight. Younger age, days of apheresis, and male gender predicted increased yield of CD34+ cells/kg donor weight. Growth factor-induced pain was mild and reported in less than 15% of patients. Most donors <20 kg (23/25, 92%) required PRBC priming of the apheresis machine. This experience with over 200 collections demonstrates that PBSC collection is safe in normal pediatric donors and desired CD34 cell yields are easily achieved. Younger children utilize more medical resources and children <20 kg usually require a single blood product exposure.

Comparison of a new WBC-reduction system and the standard plateletpheresis protocol in the same donors.

BACKGROUND: A cell separator (Spectra, Gambro BCT) with an integrated leukoreduction system (LRS) for producing WBC-reduced single-donor platelet concentrates has been shown to result in a slightly reduced collection efficiency as compared to the former Spectra system without LRS. A novel modified system for improved collection efficiencies (LRS Turbo, Gambro BCT) was evaluated. STUDY DESIGN AND METHODS: Each of 37 donors underwent plateletpheresis using the LRS Turbo (LRS-T) and the standard LRS (LRS) of the Spectra cell separator. The collection efficiency and WBC contamination of the different techniques were compared. Platelets were counted automatically and WBCs were counted by using one or two full grids of a Nageotte chamber. RESULTS: The preseparation and postseparation numbers of RBCs, WBCs, and platelets, as well as the number of collected platelets, did not differ for the two techniques. In the LRS-T separations, the collection efficiency was 112 percent of that in the LRS procedures. Median residual WBCs in the platelet components were 0.0256 x 10(6) per LRS-T procedure and 0.0253 x 10(6) per LRS procedure. The purity of the LRS-T components was not less than that of the standard LRS components, whereas the collection efficiency of the LRS-T was significantly greater, 44.9 percent versus 40.7 percent. CONCLUSIONS: The LRS-T procedures produced platelet concentrates with WBC-reduction capacity that is comparable to that obtained with the standard LRS procedures, which have previously been described as satisfying the most stringent criteria for WBC-reduced platelets. The new technique significantly improved the collection efficiency of the plateletpheresis procedure.

Lymphocytapheresis.

Leukocytapheresis has long been performed with the centrifugal method. But in 1989 in Japan, the Asahi Medical Co. developed the extracorporeal leukocyte-removal filter, Cellsorba. This filter consists of non-woven fabric, which can remove leukocytes from whole blood during extracorporeal circulation. In the incipient stage, this filter was applied to collagen diseases, rheumatoid arthritis, and systemic lupus erythematosus. During the following studies, this filter has been found to have an immunosuppressive effect. Now, it is beginning to be applied to various kinds of autoimmune diseases. Moreover, this filter has recently been recognized to be effective in inflammatory bowel diseases, ulcerative colitis, and Crohn's disease. The outline of Cellsorba and the application of this filter is described here.

An overview of leukocyte depletion in blood transfusion.

The importance of removing leukocytes from the blood before transfusion has been recognized, but the complete value has not yet been totally ascertained. In this article, past accomplishments are reviewed and future uses are outlined.